Most outboard motors, including the electric motors customarily used for trolling, are also used to steer the boat by turning the motor itself. In the case of electric fishing motors, a motor-propeller assembly is supported at the bottom of a turnable motor tube so that turning the motor-propeller assembly will steer the boat. Usually, the steering function is done manually, the units being provided with a control housing at the upper end of the motor tube which has a control handle that is used to control speed and which can also be used to steer the boat. In some instances, the steering function can be performed from a remote location using a cable or linkage system. An example of such a remote steering system is shown in U.S. Pat. No. 4,565,529 issued to Aertker et al. There are obvious disadvantages to the manual system since the operator must sit near the bow of the boat (if the motor is bow-mounted) and operate the controls. Remote systems such as the one shown and described in the foregoing identified U.S. Pat. No. 4,565,529 permit the operator to be located at various positions throughout the boat, and most remote systems utilize foot controls to free the hands of the operator for fishing. However, known remote systems, including those of the type shown in the Aertker et al patent previously referred to, are relatively complicated and require the use of cables or other linkage to turn the motor tube in order to steer the boat.
In the co-pending patent application of James R. Edwards, U.S. Ser. No. 886,517, filed July 16, 1986 entitled "Friction Steering Drive System For Electric Fishing Motors" there is described a steering drive system which utilizes a steering drive motor and gear train that drives a steering gear having a friction drive hub through which the motor tube extends. Thus, when the steering drive motor is actuated, the steering drive gear will turn at a predetermined speed and thus turn the motor tube through the friction drive. For a friction drive system of this and similar types, it is necessary to limit the rotation of the steering gear so that the operator will not inadvertently maintain the power to the steering drive motor and cause the steering gear to continue to rotate in one direction causing the battery cable to wrap around the motor tube and limit the steering or damage the battery cable. There is therefore a need for a control for limiting the movement of the steering gear while still permitting a wide range of turning in both forward and reverse.